To efficiently use limited frequency resources, there has been constructed a communication environment that may support different radio communication systems in the same frequency band and support different communication schemes in a single terminal.
When a predetermined radio communication system desires to operate, it may be difficult for the radio communication system to be aware of an environment of a frequency band that the radio communication system desires to use, which may interfere with a communication of another radio communication system.
To solve the above issue, a conventional radio communication system may need to inspect in advance a frequency band to be used and may pre-determine whether the frequency band is being used by another radio communication system, prior to initiating a communication of the radio communication system.